The labels on the horizontal axis in Figure 28.9 do not represent 10 consecutive days, but the box-and-whiskers plots are evenly spaced.

In order to treat the group variable as continuous, you can specify the CONTINUOUS or HAXIS= option when producing traditional graphics. Either option produces a box plot with a horizontal axis scaled for continuous
group variable values. (ODS Graphics does not support a continuous group axis.)

The following statements produce the plot shown in Figure 28.10. The TURNHLABELS option orients the horizontal axis labels vertically so there is room to display them all.